Targeted sequencing of patients affected by familial or sporadic Alzheimer's disease
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ABSTRACT:
PROVIDER: EGAS00001003856 | EGA |
REPOSITORIES: EGA
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Project description:Our understanding of Alzheimer’s disease (AD) pathogenesis is currently limited by difficulties in obtaining live neurons from patients and the inability to model the sporadic form of AD. It may be possible to overcome these challenges by reprogramming primary cells from patients into induced pluripotent stem cells (iPSCs). We reprogrammed primary fibroblasts from two patients with familial AD (both caused by a duplication of APP1, APPDp), two with sporadic AD (sAD1, 2) and two non-demented control individuals (NDCs) into iPSC lines. Neurons from differentiated cultures were FACS-purified and characterized. Purified cultures contained >90% neurons, clustered with fetal brain mRNA samples by microarray criteria, and could form functional synaptic contacts. Virtually all cells exhibited normal electrophysiological activity. Relative to controls, iPSC-derived, purified neurons from the two APPDp patients and patient sAD2 exhibited significantly higher levels of secreted Aβ1-40, phospho-tauThr231 (pTau) and active GSK3β (aGSK3β). Neurons from APPDp and sAD2 patients also accumulated large Rab5-positive early endosomes compared to controls. Treatment of purified neurons with β-secretase inhibitors, but not g-secretase inhibitors, caused significant reductions in pTau and aGSK3β levels. These results suggest a direct relationship between APP proteolytic processing, but not Aβ, in GSK3β activation and tau phosphorylation in human neurons. Additionally, we observed that neurons with the genome of one sAD patient exhibited the phenotypes seen in familial AD samples. More generally, we demonstrate that iPSC technology can be used to observe phenotypes relevant to AD, even though it can take decades for overt disease to manifest in patients. Total RNA extracted from normal hIPSCs, Alzheimer's patient derived hIPSCs, neurons differentiated from hIPSCs, fetal brain, fetal heart, fetal liver and fetal lung
2012-01-06 | E-GEOD-34879 | biostudies-arrayexpress
Project description:Most patients with pharmacoresistant mesial temporal lobe epilepsy (MTLE) have hippocampal sclerosis on the postoperative histopathological examination. Although most patients with MTLE do not refer to a family history of the disease, familial forms of MTLE have been reported. We studied surgical specimens from patients with MTLE who had epilepsy surgery for medically intractable seizures. We assessed and compared messenger RNA (mRNA) expression profiles of the tissue lesion found in patients with familial MTLE (n = 3) and sporadic MTLE (n = 5). In addition, we used data from control hippocampi obtained from a public database (n = 7). We obtained expression profiles using the Human Genome U133 Plus 2.0 (Affymetrix) microarray platform. Overall, the molecular profile identified in familial MTLE was distinct from that found in sporadic MTLE. In the tissue of patients with familial MTLE, we found an over-representation of the biological pathways related to protein response, mRNA processing, and synaptic plasticity and function. In sporadic MTLE, the gene expression profile suggests that the inflammatory response is highly activated. We also found enrichment of gene sets involved in inflammatory cytokines and mediators and chemokine receptor pathways in both groups. However, in sporadic MTLE, we also found enrichment of epidermal growth factor signaling, prostaglandin synthesis and regulation, and microglia pathogen phagocytosis pathways. Furthermore, based on the gene expression signatures, we identified different potential compounds to treat patients with familial and sporadic MTLE. To our knowledge, this is the first study assessing the mRNA profile in surgical tissue obtained from patients with familial MTLE and comparing it with sporadic MTLE. Our results clearly show that, despite phenotypic similarities, both forms of MTLE present distinct molecular signatures, thus suggesting different underlying molecular mechanisms that may require distinct therapeutic approaches.
2022-05-09 | GSE202101 | GEO
Project description:We have performed gene expression microarray analysis of two types of dementia, Alzheimer's disease (AD) and frontotemporal dementia (FTD), using two kind of samples, frozen brain tissue and lymphoblastoid cell lines.
2022-12-12 | GSE195872 | GEO
Project description:Rationale: Idiopathic interstitial pneumonia (IIP) and its’ familial variants are progressive and largely untreatable disorders with poorly understood molecular mechanisms. Both the genetics and the histologic type of IIP play a role in understanding the etiology and pathogenesis of interstitial lung disease, but transcriptional signatures of these subtypes are unknown. Objectives: To evaluate gene expression in the lung tissue from patients with usual interstitial pneumonia (UIP) and non-specific interstitial pneumonia (NSIP) that were either familial or non-familial in origin and compare them to gene expression from normal lung parenchyma. Methods: We profiled RNA from lungs of 16 patients with sporadic IIP, 10 with familial IIP, and 9 normal controls on a whole human genome oligonucleotide microarray. Results: Significant transcriptional differences exist in familial and sporadic IIPs. The genes distinguishing the genetic subtypes belong to the same functional categories as transcripts that distinguish IIP from normal samples. Relevant categories include chemokines and growth factors and their receptors, complement components, genes associated with cell proliferation and death, and genes in the Wnt pathway. Keywords: disease state analysis
2006-10-01 | GSE5774 | GEO
Project description:Comparison of the effects of mutaions modelling early-onset familial Alzheimer's disease and Sanfilippo syndrome childhood dementia in zebrafish larvae
| PRJNA898346 | ENA
Project description:Alzheimer's disease (AD) is the most common form of dementia, characterized by progressive cognitive impairment and neurodegeneration as a result of abnormal neuronal loss. To elucidate the molecular systems associated with AD, we characterized the gene expression changes associated with multiple clinical and neuropathological traits in 1,053 postmortem brain samples across 19 brain regions from 125 persons dying with varying severities of dementia and variable AD-neuropathology severities.
2016-08-19 | GSE84422 | GEO
Project description:Induced pluripotent stem cell (iPSC) disease models have been generated for a number of diseases, and some have shown their potential utilization for pathological and drug toxicological evaluations. We have generated two hiPSC clones from a non-familial Alzheimerâs patient (AD-iPSCs), which expressed typical undifferentiated markers and fulfilled standard pluripotency assays. Genome-wide microarray analysis revealed that AD-iPSCs are highly similar to control hiPSCs and hESCs, albeit with some noticeable differences in several genes: DNAJC15, GRPR, NAIP and SNORD116-18. Several other biomarkers were differentially expressed in AD-iPSC clones, which were implicated in memory impairment and AD. Furthermore, well characterized familial AD-associated genes (APP, PSEN1, PSEN2) and non-familial (A2M, APOE, GAP43, MAOA, MPO, PLAT, PLAU, SORL1, SNCA) exhibited different expression patterns but were largely reset upon reprogramming into a pluripotent state. Overall, hiPSCs can be good candidates for AD modeling and may represent an in vitro alternative to studying disease mechanisms and drug discovery/toxicology studies. Fibroblasts and two hiPSC clones from a non-familial Alzheimerâs patient (AD-iPSCs) were analyzed. For each cell sample, 2-3 biological replicates were obtained.
2015-12-31 | E-GEOD-31163 | biostudies-arrayexpress
Project description:Cognitively normal brains are compared to sporadic AD and Down syndrome brains with AD for comparison of two different forms of Alzheimer's disease
2024-06-30 | E-MTAB-14179 | biostudies-arrayexpress
Project description:Cerebrospinal fluid proteomic profiling reflects biological heterogeneity of early-onset Alzheimer's disease dementia from The First Affiliated Hospital of USTC
2023-02-16 | PXD040216 |
Project description:Alzheimer’s disease (AD) is the most common neurodegenerative dementia. Around 10% of cases present an age of onset before 65 years-old, which in turn can be divided in monogenic or familial AD (FAD) and sporadic early-onset AD (EOAD). Mutations in PSEN1, PSEN2 and APP genes have been linked with FAD. The aim of our study was to describe the brain whole-genome RNA expression profile of the posterior cingulate area in EOAD and FAD caused by PSEN1 mutations (FAD-PSEN1). 14 patients (7 EOAD and 7 FAD-PSEN1) and 7 neurologically healthy controls were selected and samples were hybridized in a Human Gene 1.1 microarray from Affymetrix. When comparing controls with EOAD and controls with FAD-PSEN1, we found 3183 and 3351 differentially expressed genes (DEG) respectively (FDR corrected p<0.05). However, any DEG was found in the comparison of the two groups of patients. Microarrays were validated through quantitative-PCR of 17 DEG. In silico analysis of the DEG revealed an alteration in biological pathways related to calcium-signaling, axon guidance and long-term potentiation (LTP), among others, in both groups of patients. These pathways are mainly related with cell signalling cascades, synaptic plasticity and learning and memory processes. In conclusion, the altered biological final pathways in EOAD and FAD-PSEN1 are highly coincident. Also, the findings are in line with those previously reported for late-onset AD (LOAD, onset >65 years-old), which implies that the consequences of the disease at the molecular level are similar in the final stages of the disease. 21 Samples were analyzed: 7 controls, 7 Early-onset Alzheimer's disease (AD) patients and 7 early-onset AD genetically determined by a mutation in PSEN1 gene.
2015-01-20 | E-GEOD-39420 | biostudies-arrayexpress